Fixed Amount Discharge Container

ABSTRACT

A fixed amount discharge container includes: a syringe barrel  3;  and a piston  8  inserted in the syringe barrel  3  so as to be movable in a longitudinal direction, thereby defining a fluid chamber between the syringe barrel  3  and the piston  8.  One of the syringe barrel  3  and the piston  8  includes a guide  3   c  that is extended in a longitudinal direction. The other of the syringe barrel  3  and the piston  8  includes a slider  9  that is movable in the guide  3   c  along with the other of the syringe barrel  3  and the piston  8.  The guide  3   c  is provided with a target position contact portion  3   j  which the slider  9  contacts when an amount of the fluid chamber is equal to a target amount.

TECHNICAL FIELD

The invention relates to a fixed amount discharge container including apiston that is slidably provided within a syringe barrel.

BACKGROUND ART

A syringe is as an example of a container that ejects a predeterminedamount of fluid. The syringe is structured so as to be able toadminister a given amount of medical solution required for dispensing.

The example is a syringe described in Patent Document 1. In the syringedescribed in Patent Document 1, a scale for measuring an amount ofmedical solution required for dispensing is provided on an outerperiphery of a syringe barrel. Dispensing can be practiced easily,accurately by aligning a piston to the scale.

RELATED ART DOCUMENT Patent Document

Patent Document 1: JP-A-2001-299913

SUMMARY OF INVENTION Technical Problem

As above, in order to draw in a required amount of medical solution, thesyringe described in Patent Document 1 requires accurately aligning thepiston to the scale provided on the outer periphery of the syringebarrel. For this reason, a user must pay attention to the piston and thescale at all times while consciously performing visual verification.Moreover, the amount of fluid to be drawn in varies from one user toanother.

Accordingly, an object of the invention is to provide a fixed amountdischarge container capable of easily ejecting a predetermined amount offluid at all times.

Solution To Problem

In light of the problem, a fixed amount discharge container according tothe invention comprises:

a syringe barrel; and

a piston, inserted in the syringe barrel so as to be movable in alongitudinal direction, thereby defining a fluid chamber between thesyringe barrel and the piston, wherein

one of the syringe barrel and the piston includes a guide that isextended in a longitudinal direction;

the other of the syringe barrel and the piston includes a slider that ismovable in the guide along with the other of the syringe barrel and thepiston; and

the guide is provided with a target position contact portion which theslider contacts when a amount of the fluid chamber is equal to a targetamount.

According to the invention, the fixed amount discharge container may beconfigured such that:

the guide includes a plurality of grooves;

the grooves that are adjacent to each other are formed such that axiallines of the grooves differ from each other; and

the grooves that are adjacent to each other are connected at aconnecting portion; and

a wall of the connecting portion that extends in a circumferentialdirection is performed as the target position contact portion.

According to the invention, the fixed amount discharge container may beconfigured such that:

the guide is formed in the syringe barrel as a through hole thatpenetrates through the syringe barrel in a radial direction; and

the slider is removably attached to the piston from the outside thesyringe barrel.

Further, according to the invention, the fixed amount dischargecontainer may comprise an adaptor that changes the target amount.

Advantageous Effects of Invention

The fixed amount discharge container of the invention allows the user toascertain a point in time when the amount of the fluid chamber filledwith fluid has become equal to the target amount from the fact that theslider has contacted the target position contact portion. Therefore, itis possible to provided a fixed amount discharge container that canreadily, accurately eject a target amount of fluid at all times.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view of an entire syringe of an embodimentbefore a medicine is drawn and after the medicine is dispensed.

FIG. 2 is a longitudinal cutaway side view of the syringe shown in FIG.1.

FIG. 3 is an exploded perspective view of the syringe shown in FIG. 1.

FIG. 4 is a perspective view of the entire syringe that is shown in FIG.1 and acquired after it finishes drawing in a medicine.

FIG. 5 is a perspective view of the entire syringe that is shown in FIG.1 and acquired after completion of bubble removal shown in FIG. 1.

FIG. 6 is a perspective view of the entire syringe that is shown in FIG.1 and acquired before dispensing.

FIG. 7 is a perspective view of a modification of a slider.

FIG. 8 is a perspective view of another modification of the slider.

FIG. 9 is a perspective view of still another modification of theslider.

FIG. 10 is a cutaway side view of the syringe of the modification.

FIG. 11 is a front view of the syringe of the other modification.

FIG. 12 is a perspective view of an adaptor to be attached to thesyringe.

FIG. 13 is a cutaway side view of the syringe outfitted with the adaptorshown in FIG. 12.

DESCRIPTION OF EMBODIMENTS

An embodiment in which a fixed amount discharge container of theinvention is applied to a syringe 1 is now described by reference toFIG. 1 to FIG. 6.

The syringe 1 of the embodiment is made up of an injection needle set 2,a syringe barrel 3, and a piston set 4. The injection needle set 2 isscrew-engaged with a front part of the syringe barrel 3. In theinjection needle set 2, a needle 5 is fixedly press-fitted to a needlebase 6. An inner diameter portion 6 a of the needle base 6 and a rib 3 aof the syringe barrel 3 are fixedly press-fitted together, therebypreventing a medical solution from leaking out from any other locationexcept a tip end of the injection needle. The needle 5 is formed fromstainless steel, and the needle base 6 is formed from PP(polypropylene).

The syringe barrel 3 is a substantially tubular member that extends inits longitudinal direction. The piston set 4 is inserted into an innerdiameter portion 3 b of the syringe barrel 3 so as to be movable in thelongitudinal direction of the syringe barrel 3. A fluid chamber isdefined between the syringe barrel 3 and a tip end of a plunger 7 of thepiston set 4. A amount of the fluid chamber can be changed by moving thepiston set 4 with respect to the syringe barrel 3.

An outer diameter projection 7 a of the plunger 7 is press-fitted intothe inner diameter portion 3 b of the syringe barrel 3 in a slidablefashion. The plunger 7 is formed from butyl rubber, which is a softmember, and capable of compression and deformation. This prevents amedical solution from leaking out from clearance between the plunger 7and the inner diameter portion 3 b of the syringe barrel 3. In order toenhance slidability to a much greater extent, silicon is applied on anouter periphery of the plunger 7. The syringe barrel 3 is formed from PP(polypropylene).

A configuration of the piston set 4 is now described. The plunger 7positioned in front of a piston 8 is fixed to the piston 8 such that aninner diameter concave 7 b of the plunger 7 and a front end projection 8a of the piston 8 are rotatable with respect to the longitudinaldirection of the syringe barrel 3.

The slider 9 is press-fitted into an insertion hole 8 b of the piston 8formed in a vertical direction with respect to the longitudinaldirection of the syringe barrel 3. The piston 8 is formed from PP(polypropylene), and the slider 9 is formed from PP (polypropylene).

The slider 9 is configured to be movable with respect to thelongitudinal direction of the syringe barrel 3 along a guide 3 c of thesyringe barrel 3 by moving the piston set 4 with respect to the syringebarrel 3. The slider 9 is configured to be movable also in a peripheraldirection of the syringe barrel 3.

A method for operating the syringe 1 is now described. Operation of thesyringe 1 includes three operations; namely, suction, bubble removal,and dispensing.

In a state of the syringe 1 achieved before being used; namely, a stateacquired before the syringe 1 draws in a medical solution from a vial bysuction, the slider 9 remains in contact with a front end 3 e of a firstgroove 3 d as illustrated in FIG. 1. In short, the piston set 4 issituated at the foremost end.

Next, the piston set 4 is pulled backward with respect to the syringebarrel 3 in order to draw in the medical solution from the vial,whereupon the slider 9 comes into contact with a slope 3 f. The slider 9then moves to a second groove 3 g while turning along the slope 3 f.When the piston set 4 is continuously pulled backward furthermore, theslider 9 contacts a rear end face 3 h of the second groove 3 g asillustrated in FIG. 4, whereupon the piston set 4 is situated at arearmost end of the movable range. The slider 9 is at this time fixed toa guide member 3 c by means of a rib 3 i projecting toward an interiorof the guide 3 c while the slider 9 remains in a slightly press-fittedstate. After completion of suction in this state, an interior of thefluid chamber becomes filled with the medical solution.

Since the slider 9 remains in contact with a rear end face 3 h of theguide 3 c, the piston set 4 will not move backward any further.Specifically, there is no fear that the piston set 4 might get out ofthe syringe barrel 3 in a backward direction.

In addition, so long as the injection needle set 2 is removed in thisstate and provided with a cap instead, sterilized, and packaged, thesyringe can also be utilized as a pre-filled syringe.

Subsequently, operation for removing a bubble from the medical solutionin the fluid chamber is performed. A rear end face 8 c of the piston 8is pushed to thereby move the piston set 4 toward the front, whereuponthe slider 9 moves forwardly, decreasing the amount of the fluidchamber. Thus, the medical solution is ejected from a tip end hole 5 aof the needle 5. When the piston set 4 is additionally kept movingtoward the front, the slider 9 contacts a step (a target positioncontact portion) 3 j of the guide 3 c as illustrated in FIG. 5, so thatthe piston set 4 cannot advance any further. Removal of a bubble in thefluid chamber is completed in this state, and the fluid chamber definedbetween the syringe barrel 3 and the interior of the injection needleset 2 becomes free of air.

Dispensing operation is now performed. First, a projection 8 d of thepiston 8 is turned in a circumferential direction of the syringe barrel3. The piston 8 is thereby turned, whereupon the slider 9 moves from thesecond groove 3 g to the first groove 3 d, so that the piston set 4becomes able to move along a longitudinal direction. When the rear endface 8 c of the piston 8 is further pushed, the slider 9 advances alongthe first groove 3 d, whereupon the slider 9 contacts the front end face3 e of the first groove 3 d as illustrated in FIG. 1. The piston set 4is thereby situated at the foremost end, whereupon dispensing iscompleted. Thus, the syringe 1 enters the same state as that achievedbefore use of it.

Incidentally, the step 3 j is placed at a location where the slider 9contacts the step 3 j when the amount of the fluid chamber becomes equalto a target amount which is a amount required for dispensing. To bespecific, when the piston set 4 is moved forwards such that the slider 9moves from the step 3 j to the front end face 3 e, the target amount ofmedical solution is ejected.

As above, in the syringe 1 of the embodiment, the step 3 j is placed atthe location where the slider 9 contacts the step when the amount of thefluid chamber becomes equal to the target amount which is the amountrequired for dispensing. For this reason, so long as the user pushes therear end face 8 c of the piston 8 until the slider 9 contacts the step 3j, the amount of medical solution in the fluid chamber can be set to atarget amount. During this operation, since the user does not need topay attention by particularly viewing the scale, or the like, the amountof the fluid chamber can be set to a target amount by simple operation.In addition, the operation does not require proficiency. Whoever theuser is, he/she can set the amount of the fluid chamber to a targetamount at all times by handling the syringe 1.

In the syringe 1 of the embodiment, a distance between the rear end face3 h and the step 3 j of the guide 3 c remains constant at all times.Specifically, since a range in which the slider 9 moves from a locationwhere suction of the solution is completed to a location where removalof a bubble is completed is constant, the amount of medical solutionejected during operation for removing a bubble is also constant all ofthe time. Consequently, the medical solution can constantly used in anappropriate amount by appropriately setting distance between the rearend face 3 h and the step 3 j. An excessive amount of medical solutionhas hitherto been disposed in order to assure removal of a bubble, andthe medical solution has been wasted. The syringe 1 of the embodiment,however, prevents wasteful use of a medical solution.

Although the invention has been described thus far by use of itsembodiment, a technical scope of the invention is not restricted to thescope defined by the embodiment. It is manifest to those who are versedin the art that the embodiment be susceptible to a variety ofalterations or modifications.

For instance, in the first embodiment, the method for fixing theinjection needle set 2 is screw-engagement, and the end of the tube ofthe syringe barrel 3 has a thread shape. However, the injection needleset 2 can also be fixed by means of a Lure syringe method (i.e., aplug-in method) as in the case of a common syringe. In addition, thesyringe barrel 3 can also be formed from a resin material, like PP(polypropylene), PE (polyethylene), and PET (polyethylene terephthalate)or a hard material made of stainless steel or glass.

In addition, although the slider 9 has a rectangular shape in theembodiment, the slider is not limited to the shape. The slider 9 canalso assume; for instance, a square shape, a circular shape, an ovalshape, or a gourd shape. Thus, the shape of the slider 9 is selectableas necessary.

Furthermore, the syringe barrel 3, the needle base 6, and the piston 8are molded from a transparent resin, and the plunger 7 and the slider 9are molded from an opaque, color resin in the embodiment. However, thesyringe barrel 3, the needle base 6, and the piston 8 can also be moldedfrom the opaque, color resin, and the plunger 7 and the slider 9 canalso be molded from the transparent resin. Moreover, opaque resins ortransparent resins can also be used for both, or semi-transparent resinscan be used. Further, combinations of them are also selectable asrequired.

Although the syringe barrel 3, the needle base 6, the piston 8, and theslider 9 employ as a material a PP (polypropylene) resin in thepreceding embodiment, a PE (polyethylene), or the like, can also beused. Moreover, although the plunger 7 uses butyl rubber, butadienerubber, silicone rubber, an elastomer resin can also be used. Thus, thematerial of the plunger 7 can be selected appropriately depending on asituation where the plunger is to be used.

Various modifications of the shape of the slider 9 are now mentioned byreference to FIG. 7 to FIG. 10. In the embodiment, the slider 9 has ashape so that the slider 9 is press-fitted to the piston 8 so as not toget out of the piston 8. However, the shape of the slider 9 is notlimited to this shape. The slider 9 can also has another shape; forinstance, an arrow shape with a rotation stop as shown in FIG. 7; ashape including an arrow shape with a rotation stop and a slit, as shownin FIG. 8; a shape that is a combination of an arrow shape with arotation stop and a C-shaped ring as shown in FIG. 9; and a shape inwhich the slider 9 is integrated with the piston 8 as shown in FIG. 10.

Features of the respective shapes are as follows. The arrow shape with arotation stop shown in FIG. 7 is configured to prevent the slider 9 fromgetting out of the piston 8 by the arrow shape thereof. The shape shownin FIG. 8 that includes the arrow shape with a rotation stop and theslit is embodied by adding a slit to the shape shown in FIG. 7. By meansof the slit, a tip end of the slider 9 becomes deformed during assemblyof the syringe 1, thereby facilitating insertion of the piston 8 intothe insert hole 8 b.

Likewise, even in the shape shown in FIG. 9 that is a combination of thearrow shape with a rotation stop and the C-shaped ring, the tip end ofthe slider 9 becomes deformed during assembly by means of the C-shapedring, thereby facilitating insertion of the piston 8 into the inserthole 8 b.

The shape shown in FIG. 10 that integrates the slider 9 and the piston 8together corresponds to a single component into which the slider 9 andthe piston 8 are integrated. A notch is formed on the back of aprojecting portion around an outer periphery of the slider 9, and theslider 9 is made elastically deformable within a space defined by thenotch. When the piston set 4 is inserted from the back of the syringebarrel 3, the piston set 4 is inserted while the slider 9 of the piston8 becomes elastically deformed, so that assembly is facilitated.

Moreover, explanations are given to the embodiment by taking the examplein which the guide 3 c includes the first groove 3 d and the secondgroove 3 g. However, the guide 3 c can also be given multiple steps,such as three steps and four steps. In addition, the shape of the guide3 c can also be a circular arc shape or a spline curve rather than alinear shape. The shape of the guide 3 c is now specifically describedby reference to FIG. 11.

FIG. 11 is a front view of the syringe 1 of the modification of theinvention. In the modification, the guide 3 c has a first groove 3 d, asecond flue 3 g, and a third groove 3 l. The three grooves 3 d, 3 g, and3 l are formed such that adjacent grooves have respective differentaxial lines. In addition, the first groove 3 d and the second groove 3g, which are adjacent to each other, are connected at a first connectingportion 3 n, and the first groove 3 d and the third groove 3 l, whichare adjacent to each other, are connected at a second connecting portion3 o.

The first connecting portion 3 n and the second connecting portion 3 oare formed as spaces that extend along the peripheral direction of thesyringe barrel 3. Further, portions of the wall that make up the firstconnecting portion 3 n and the second connecting portion 3 o are formedas the first step 3 j and a second step 3 e.

The first step 3 j is placed at a location where the slider 9 contactsthe step 3 j when the amount of the fluid chamber becomes equal to thefirst target amount during movement of the slider 9 through an interiorof the second groove 3 g. The second step 3 e is placed at a locationwhere the slider 9 contacts the step 3 e when the amount of the fluidchamber becomes equal to the second target amount during movement of theslider 9 through an interior of the first groove 3 d. Further, a frontend face 3 m is placed at a location where the slider 9 contacts thefront end face when the amount of the fluid chamber becomes equal to thethird target amount during movement of the slider 9 through an interiorof the third groove 3 l.

The piston 8 is moved such that the slider 9 moves from the rear endface 3 h through the interior of the second groove 3 g until the slidercontacts the first step 3 j, whereby the medical solution can thereby beejected in the first target amount. Furthermore, when the piston 8 isturned and moved in the longitudinal direction such that the slider 9moves from the first step 3 j through the interior of the first groove 3d in the circumferential direction, the medical solution can be ejectedin the second target amount. Likewise, the piston 8 is moved such thatthe slider 9 moves from the second step 3 e through the interior of thethird groove 3 l in the circumferential direction, whereby the medicalsolution can be ejected in the third target amount.

In the syringe 1 of the modification, when the slider 9 is moved throughthe interior of each of the first groove 3 d, the second groove 3 g, andthe third groove 3 l, the piston 8 is moved in the longitudinaldirection. In the meantime, when the slider 9 is moved from the secondgroove 3 g to the first groove 3 d, the piston 8 must be turned alongthe circumferential direction in order to let the slider 9 pass throughthe first connecting portion 3 n. As above, in order to let the slider 9move from the second groove 3 g to the first groove 3 d, the directionof movement of the piston 8 must be changed. By the above configuration,since the slider 9 from continually moves from the second groove 3 g tothe first groove 3 d, the first target amount of medical solution andthe second target amount of medical solution can be ejected whiledistinguished from each other with certainty.

Such a configuration enables accurate ejection of a predetermined amountof medical solution in each of the steps during multi-step ejectionoperation. The respective steps can be separately used for specifictargets. For instance, the first target amount can be used for infants;a total amount consisting of the first target amount and the secondtarget amount can be used for children at and under the age of 12; and atotal amount consisting of the first target amount, the second targetamount, and the third target amount can be used for adults. One syringe1 can thereby administer an accurate amount of medicine to a person nomatter how old the person is or no matter what physique the person has.Further, the first target amount, the second target amount, and thethird target amount can be set to an equal amount or to differentamounts, respectively.

The respective grooves 3 d, 3 g, and 3 l of the guide 3 c can have acircular arc shape or a spline curve rather than a linear shape. When aperson pushes an object, pushing action is performed while using manyarticulations, like fingers and a wrist of the person. For thesereasons, the locus of pushing action is not straight, and pushing isperformed while being slightly curved. The shape of the guide 3 c is acircular shape or a spline curve in alignment with the locus of thehuman action, whereby operability of the syringe 1 is enhanced.

Moreover, the embodiment has been described by taking as an example theslider 9 that projects outside the syringe barrel 3. However, the slider9 can also be accommodated within the syringe barrel 3. In this case,there is adopted a structure in which the piston 8 is provided with aguide; in which a projection that projects toward the piston 8 isprovided on an inner diameter portion of the syringe barrel 3; and inwhich the guide on the piston is caused to fit into the projection. Bymeans of the structure, the slider will not appear outside, so that theappearance of the syringe is improved.

Also, the embodiment has been described by taking an example in whichthe syringe barrel 3 is provided with the guide 3 c and in which theslider 9 is attached to the piston 8. However, the invention is notlimited to the embodiment. The syringe barrel 3 can also be providedwith a slider, and the piston 8 can also be provided with a guide.

An adaptor 10 that can be used while attached to the syringe 1 and isconfigured to change an ejection amount is now described by reference toFIG. 12 and FIG. 13. FIG. 12 is a perspective view of an adaptor to beattached to a syringe. FIG. 13 is a cutaway side cross sectional view ofthe syringe outfitted with the adaptor shown in FIG. 12.

The adaptor 10 is a member to be removably attached to a periphery ofthe syringe barrel 3. The projection 10 a provided on an inner peripheryof the adaptor 10 fits into the first groove 3 d of the syringe barrel3, thereby contacting the front end face 3 e. Ribs 10 b are provided onthe inner periphery of the adaptor 10. As a result of the syringe barrel3 being caught by the rigs 10 b, the adaptor 10 is stationarily fixedwhile being lightly press-fitted to the outer periphery of the syringebarrel 3.

The projection 10 a of the adaptor 10 prevents any further advancementof the slider 9 at a position in front of the front end face 3 e. Bymeans of a simple technique that allows attachment of the adaptor 11,the target amount can thereby be set to a smaller value. Further, thetarget amount can readily changed by changing the size of the adaptor10.

The adaptor and the syringe are screw-engaged together and made movablein the longitudinal direction thereof, whereby the adaptor can be fixedat an arbitrary position. Thus, a container capable of ejecting apredetermined amount of various solutions is obtained.

In the embodiment, the invention has been described by taking as anexample a syringe with an injection needle. However, the invention isnot limited to the embodiment. The fixed amount discharge container ofthe invention is a container that can draw in and eject a predeterminedtarget amount of solution. Hence, the fixed amount discharge containercan be used as a container for administering a medicinal drink forinfants, a container that draws in, by suction, and ejects a cosmeticaroma oil, a container utilized for refilling a vial with perfume wateror personally blending perfume waters, or a container used for nursing asmall animal or providing water to the small animal.

In addition, so long as the guide is given multiple steps, such as threesteps and four steps, the syringe becomes useful in a case where achange is made to conditions for experiment of falling a predeterminedamount of test reagent on a Petri dish, such as falling one milliliterof test reagent up to a second step and two milliliters of test reagentup to a third step.

The guide 3 c is formed as a through hole that penetrates through thesyringe barrel 3 in its radial direction; the shape of the slider 9 isset as illustrated in FIG. 7 to FIG. 10; and the slider 9 is removablyattached to the piston 8. Assembly of the fixed amount dischargecontainer thereby becomes facilitated. Furthermore, since disassembly ofthe fixed amount discharge container is also easy, the fixed amountdischarge container can be recycled by disassembling the dispenser,cleansing parts, and reassembling the parts.

Although the invention has been specifically described with reference tothe specific illustrative embodiments, it is apparent to one skilled inthe art that a variety of changes and modifications can be made withoutdeparting from the spirit and scope of the invention.

This application is based on Japanese Patent Application No. 2011-098003filed on Apr. 25, 2011, the disclosures of which are incorporated hereinby way of reference.

INDUSTRIAL APPLICABILITY

The fixed amount discharge container of the invention allows the user toascertain a point in time when a amount of a fluid chamber filled withfluid becomes equal to a target amount from the fact that a slider hascontacted a target position contact portion. Accordingly, the inventioncan provide a fixed amount discharge container that can readily,accurately eject fluid in a target amount at all times.

1. A fixed amount discharge container comprising: a syringe barrel; anda piston, inserted in the syringe barrel so as to be movable in alongitudinal direction, thereby defining a fluid chamber between thesyringe barrel and the piston, wherein one of the syringe barrel and thepiston includes a guide that is extended in a longitudinal direction;the other of the syringe barrel and the piston includes a slider that ismovable in the guide along with the other of the syringe barrel and thepiston; and the guide is provided with a target position contact portionwhich the slider contacts when an amount of the fluid chamber is equalto a target amount.
 2. The fixed amount discharge container as set forthin claim 1, wherein the guide includes a plurality of grooves; thegrooves that are adjacent to each other are formed such that axial linesof the grooves differ from each other; the grooves that are adjacent toeach other are connected at a connecting portion; and a wall of theconnecting portion that extends in a circumferential direction isperformed as the target position contact portion.
 3. The fixed amountdischarge container as set forth in claim 1, wherein the guide is formedin the syringe barrel as a through hole that penetrates through thesyringe barrel in a radial direction; and the slider is removablyattached to the piston from the outside the syringe barrel.
 4. The fixedamount discharge container as set forth in claim 1, further comprisingan adaptor that changes the target amount.